Reporting of multi-arm parallel-group randomized trials: Extension of the CONSORT 2010 Statement

The Consolidated Standards of Reporting Trials (CONSORT) 2010 Statement improves the reporting of randomized trials but focuses on two-arm trials. This paper presents an extension to the statement that addresses what should be reported if a trial uses a parallel-group design with three or more groups (multiarm). The extension facilitates transparent reporting that make results more useful for clinicians, journal editors, reviewers, guideline authors and funders.